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class="post-meta-label">字数总计:</span><span class="word-count">2.5k</span><span class="post-meta-separator">|</span><i class="far fa-clock fa-fw post-meta-icon"></i><span class="post-meta-label">阅读时长:</span><span>9分钟</span></span><span class="post-meta-separator">|</span><span class="post-meta-pv-cv" id="" data-flag-title="JavaScript🌞语法基础"><i class="far fa-eye fa-fw post-meta-icon"></i><span class="post-meta-label">阅读量:</span><span id="busuanzi_value_page_pv"></span></span></div></div></div><article class="post-content" id="article-container"><h1 id="JavaScript"><a href="#JavaScript" class="headerlink" title="JavaScript"></a>JavaScript</h1><ul>
<li>网站推荐：<a target="_blank" rel="noopener" href="https://www.liaoxuefeng.com/wiki/1022910821149312">JavaSript教程</a>  || <a target="_blank" rel="noopener" href="https://www.w3school.com.cn/">W3school</a>||<a target="_blank" rel="noopener" href="https://wangdoc.com/javascript/index.html?utm_source=qq&utm_medium=social&utm_oi=619975022605897728">JavaScript 教程</a>||<a target="_blank" rel="noopener" href="https://javascript.ruanyifeng.com/">JavaScript 标准参考教程（alpha）</a></li>
<li>JavaScript是一种运行在浏览器中的解释型的编程语言。</li>
<li>在Web世界里，只有JavaScript能跨平台、跨浏览器驱动网页，与用户交互.</li>
<li>JavaScript内嵌于HTML网页中,通过浏览器内置的JavaScript引擎直接编译，使静态转变成支持用户交互的页面程序。</li>
</ul>
<table>
<thead>
<tr>
<th align="center">语言</th>
<th align="center">作用</th>
<th align="center">说明</th>
</tr>
</thead>
<tbody><tr>
<td align="center"><code>HTML</code></td>
<td align="center">结构</td>
<td align="center">从语义的角度，描述页面结构</td>
</tr>
<tr>
<td align="center"><code>CSS</code></td>
<td align="center">样式</td>
<td align="center">从审美的角度，美化页面</td>
</tr>
<tr>
<td align="center"><code>JavaScript</code></td>
<td align="center">行为</td>
<td align="center">从交互的角度，提升用户体验</td>
</tr>
</tbody></table>
<h2 id="引入方式"><a href="#引入方式" class="headerlink" title="引入方式"></a>引入方式</h2><ul>
<li><strong>嵌入式</strong><br>直接编写在HTML文件中</li>
</ul>
<figure class="highlight html"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">script</span> <span class="attr">type</span>=<span class="string">&quot;text/javascript&quot;</span>&gt;</span></span><br><span class="line">	JavaScript语句</span><br><span class="line"><span class="tag">&lt;/<span class="name">script</span>&gt;</span></span><br></pre></td></tr></table></figure>

<ul>
<li> <strong>外链式</strong><br>保存在一个单独的文件中，用“js”作为文件扩展名,最好放在body标签的底部，可以减少对整个页面的下载影响</li>
</ul>
<figure class="highlight html"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">script</span> <span class="attr">src</span>=<span class="string">&quot;js/test.js&quot;</span>&gt;</span><span class="tag">&lt;/<span class="name">script</span>&gt;</span></span><br></pre></td></tr></table></figure>

<ul>
<li><strong>行内式</strong><br>将Javascript代码作为HTML标签的属性值使用</li>
</ul>
<figure class="highlight html"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">a</span> <span class="attr">href</span>=<span class="string">&quot;javascript:alert(&#x27;Hello&#x27;);&quot;</span>&gt;</span>test<span class="tag">&lt;/<span class="name">a</span>&gt;</span></span><br></pre></td></tr></table></figure>


<h2 id="异步加载"><a href="#异步加载" class="headerlink" title="异步加载"></a>异步加载</h2><ul>
<li>无论使用内嵌式还是外链式，页面的下载和渲染都会暂停，等待脚本执行完成后才会继续。为了降低阻塞问题对页面造成的影响，可以使用可选属性：<code>async</code>和<code>defer</code>,添加后，即使文件下载失败，也不会阻塞javascript代码的执行</li>
</ul>
<ul>
<li><strong>async</strong><br>async用于异步加载，即先下载文件，不阻塞其他代码执行，下载完成后再执行</li>
</ul>
<figure class="highlight html"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">script</span> <span class="attr">src</span>=<span class="string">&quot;http://js.test/file.js&quot;</span> <span class="attr">async</span>&gt;</span><span class="tag">&lt;/<span class="name">script</span>&gt;</span></span><br></pre></td></tr></table></figure>

<ul>
<li><strong>defer</strong><br>defer用于延后执行，即先下载文件，直到网页加载完成后再执行</li>
</ul>
<figure class="highlight html"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">script</span> <span class="attr">src</span>=<span class="string">&quot;http://js.test/file.js&quot;</span> <span class="attr">defer</span>&gt;</span><span class="tag">&lt;/<span class="name">script</span>&gt;</span></span><br></pre></td></tr></table></figure>
<h2 id="输出语句"><a href="#输出语句" class="headerlink" title="输出语句"></a>输出语句</h2><ul>
<li><strong>alert()</strong><br>弹出一个警告框</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">alert(<span class="string">&quot;提示信息&quot;</span>);</span><br></pre></td></tr></table></figure>
<ul>
<li> <strong>console.log()</strong><br>在浏览器的控制台中输出内容(按F12)</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="string">&#x27;你好！&#x27;</span>);</span><br></pre></td></tr></table></figure>
<ul>
<li> <strong>document.write()</strong><br>在HTML文档页面输出内容，也可以输出标签</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">document</span>.write(<span class="string">&#x27;&lt;b&gt;加粗文本&lt;/b&gt;&#x27;</span>);</span><br></pre></td></tr></table></figure>
<ul>
<li><strong>prompt()</strong><br>弹出一个输入框</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">var</span> value=prompt(<span class="string">&quot;提示输入&quot;</span>,<span class="string">&quot;默认值&quot;</span>);</span><br></pre></td></tr></table></figure>
<h1 id="数据类型"><a href="#数据类型" class="headerlink" title="数据类型"></a>数据类型</h1><ul>
<li>JavaScript 只有五种基本数据类型（<code>boolean null undefined number string</code>）和一种复杂数据类型 <code>Object</code></li>
<li>关于各种数据类型对布尔类型的转换关系。</li>
</ul>
<table>
<thead>
<tr>
<th align="center">数据类型</th>
<th align="center">转换为 true</th>
<th align="center">转换为 false</th>
</tr>
</thead>
<tbody><tr>
<td align="center"><code>boolean</code> 类型</td>
<td align="center"><code>true</code></td>
<td align="center"><code>false</code></td>
</tr>
<tr>
<td align="center"><code>string</code> 类型</td>
<td align="center">任何非空字符串</td>
<td align="center">“”(空字符串)</td>
</tr>
<tr>
<td align="center"><code>number</code> 类型</td>
<td align="center">任何非零数字值（包括无穷大）</td>
<td align="center"><code>0</code>、<code>0.0</code> 和 <code>NaN</code></td>
</tr>
<tr>
<td align="center"><code>Object</code> 类型</td>
<td align="center">任何对象</td>
<td align="center"><code>null</code></td>
</tr>
<tr>
<td align="center"><code>undefined</code></td>
<td align="center"></td>
<td align="center"><code>undefined</code></td>
</tr>
</tbody></table>
<div class="note success simple"><p>NaN 表示不是一个数字 但是属于 number 类型，与任何值不相等包括自身</p>
</div>

<h2 id="包装类型"><a href="#包装类型" class="headerlink" title="包装类型"></a>包装类型</h2><ul>
<li>在 JavaScript 语言中，原始类型与包装类型创建的数据在使用上没有任何差异</li>
<li>定义变量的两种方式</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">// 直接/字面量 量方式定义</span></span><br><span class="line"><span class="keyword">var</span> bool = <span class="literal">true</span>;</span><br><span class="line"><span class="comment">//构造函数方式</span></span><br><span class="line"><span class="keyword">var</span> Bool = <span class="keyword">new</span> <span class="built_in">Boolean</span>(<span class="literal">true</span>);</span><br></pre></td></tr></table></figure>

<ul>
<li>三种包装类型分别是 布尔类型、数字类型、字符串类类型</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">var</span> Bool = <span class="keyword">new</span> <span class="built_in">Boolean</span>(<span class="literal">true</span>);</span><br><span class="line"><span class="keyword">var</span> Num = <span class="keyword">new</span> <span class="built_in">Number</span>(<span class="number">100</span>);</span><br><span class="line"><span class="keyword">var</span> Str = <span class="keyword">new</span> <span class="built_in">String</span>(<span class="string">&quot;this is message&quot;</span>);</span><br></pre></td></tr></table></figure>

<ul>
<li>判断包装类型不能使用 <code>typeof</code> 而是使用 <code>instanceof</code> 。语法结构<code>变量名/对象名 instanceof 构造函数/数据类型</code></li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(Str <span class="keyword">instanceof</span> <span class="built_in">String</span>);</span><br></pre></td></tr></table></figure>

<h2 id="特殊类型"><a href="#特殊类型" class="headerlink" title="特殊类型"></a>特殊类型</h2><h3 id="undefined"><a href="#undefined" class="headerlink" title="undefined"></a>undefined</h3><ul>
<li>得到 <code>undefined</code> 这个值的情况</li>
<li>声明变量但未初始化值时</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">var</span> msg;</span><br><span class="line"><span class="built_in">console</span>.log(msg);</span><br></pre></td></tr></table></figure>

<ul>
<li>声明变量并初始化值为 <code>undefined</code> 时</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">var</span> msg1 = <span class="literal">undefined</span>;</span><br><span class="line"><span class="built_in">console</span>.log(msg1);</span><br></pre></td></tr></table></figure>

<ul>
<li>函数中的 return 语句的默认返回值</li>
<li>函数中的 return 语句的返回值的设置为 <code>undefined</code></li>
<li>访问某一对象中不存在的属性时</li>
</ul>
<h3 id="null"><a href="#null" class="headerlink" title="null"></a>null</h3><ul>
<li><code>null</code> 是 5 个基本类型的一个，但是得到的类型是 object。这是 JavaScript 语言的历史遗留问题 / 当初设计的纰漏。所以当我们判断 null 类型时可以使用特殊方法 </li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="built_in">Object</span>.prototype.toString.call(<span class="literal">null</span>));</span><br></pre></td></tr></table></figure>

<ul>
<li>undefined 派生于 null。他们两个值相等但类型不等。</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="literal">undefined</span> == <span class="literal">null</span>); <span class="comment">// 结果true 说明值相等</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="literal">undefined</span> === <span class="literal">null</span>); <span class="comment">// 结果false 说明类型不等</span></span><br></pre></td></tr></table></figure>


<h2 id="类型转换"><a href="#类型转换" class="headerlink" title="类型转换"></a>类型转换</h2><table>
<thead>
<tr>
<th align="center">关键点</th>
<th align="center">隐式类型转换</th>
<th align="center">显式类型转换</th>
</tr>
</thead>
<tbody><tr>
<td align="center">JavaScript 官方规范</td>
<td align="center">官方未提及</td>
<td align="center">明确表明</td>
</tr>
<tr>
<td align="center">执行效率 / 性能</td>
<td align="center">优于显式转换</td>
<td align="center">弱于隐式转换</td>
</tr>
<tr>
<td align="center">难易程度</td>
<td align="center">不易</td>
<td align="center">容易</td>
</tr>
</tbody></table>
<h3 id="隐式类型转换"><a href="#隐式类型转换" class="headerlink" title="隐式类型转换"></a>隐式类型转换</h3><table>
<thead>
<tr>
<th align="center">欲转换为</th>
<th align="center">转换符号</th>
<th align="center">说明</th>
<th align="center">示例</th>
</tr>
</thead>
<tbody><tr>
<td align="center">布尔</td>
<td align="center"><code>!!</code></td>
<td align="center">将数据转换为布尔类型，在数据前加 <code>!!</code> 即可</td>
<td align="center"><code>!!&quot;this is message&quot;</code></td>
</tr>
<tr>
<td align="center">数字</td>
<td align="center"><code>+</code></td>
<td align="center">将数据转换为数字类型，在数据前加 <code>+</code> 即可</td>
<td align="center"><code>+&quot;this is message&quot;</code></td>
</tr>
<tr>
<td align="center">字符串</td>
<td align="center"><code>&quot;&quot;+</code></td>
<td align="center">将数据转换为字符串类型，与空字符串相加即可 (位置无关)</td>
<td align="center"><code>&quot;&quot; + 100</code></td>
</tr>
</tbody></table>
<ul>
<li>如果存在字符串的话，按照字符串的拼接操作</li>
<li>没有字符串，而存在数字值的话，按照算数运算操作</li>
</ul>
<h3 id="显式类型转换"><a href="#显式类型转换" class="headerlink" title="显式类型转换"></a>显式类型转换</h3><ul>
<li>显示类型转换则是利用类型的构造方法</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">// 转化为 boolean 类型</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="keyword">typeof</span> <span class="built_in">Boolean</span>(<span class="string">&quot;this is message&quot;</span>));</span><br><span class="line"><span class="built_in">console</span>.log(<span class="keyword">typeof</span> <span class="built_in">Boolean</span>(<span class="number">100</span>));</span><br><span class="line"><span class="comment">// 转化为number类型</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="keyword">typeof</span> <span class="built_in">Number</span>(<span class="string">&quot;100&quot;</span>));</span><br><span class="line"><span class="built_in">console</span>.log(<span class="keyword">typeof</span> <span class="built_in">Number</span>(<span class="literal">true</span>));</span><br><span class="line"><span class="comment">// 转化为 string 类型</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="keyword">typeof</span> <span class="built_in">String</span>(<span class="number">100</span>));</span><br><span class="line"><span class="built_in">console</span>.log(<span class="keyword">typeof</span> <span class="built_in">String</span>(<span class="literal">true</span>));</span><br></pre></td></tr></table></figure>

<ul>
<li>关于转换为数字时 JavaScript 提供了提供了两个函数用户转换为 number 类型的整数和浮点数。</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="built_in">parseInt</span>(<span class="number">11.11</span>));</span><br><span class="line"><span class="built_in">console</span>.log(<span class="built_in">parseFloat</span>(<span class="number">11.11</span>));</span><br></pre></td></tr></table></figure>

<ul>
<li>但需要注意的是：转换为整型即 <code>parseInt</code> 函数，如果包含小数则将小数部分舍掉，并不会四舍五入计算。</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="string">&quot;100转化为&quot;</span>, <span class="built_in">parseInt</span>(<span class="string">&quot;100&quot;</span>));</span><br><span class="line"><span class="built_in">console</span>.log(<span class="string">&quot;100.55转化为&quot;</span>, <span class="built_in">parseInt</span>(<span class="string">&quot;100.55&quot;</span>));</span><br><span class="line"><span class="built_in">console</span>.log(<span class="string">&quot;100转化为&quot;</span>, <span class="built_in">parseFloat</span>(<span class="string">&quot;100&quot;</span>));</span><br><span class="line"><span class="built_in">console</span>.log(<span class="string">&quot;100.55转化为&quot;</span>, <span class="built_in">parseFloat</span>(<span class="string">&quot;100.55&quot;</span>));</span><br><span class="line"><span class="comment">/*</span></span><br><span class="line"><span class="comment">输出结果为：</span></span><br><span class="line"><span class="comment">100转化为 100</span></span><br><span class="line"><span class="comment">100.55转化为 100</span></span><br><span class="line"><span class="comment">100转化为 100</span></span><br><span class="line"><span class="comment">100.55转化为 100.55</span></span><br><span class="line"><span class="comment">*/</span></span><br></pre></td></tr></table></figure>

<ul>
<li>关于转换为 string 类型 JavaScript 还提供一个 <code>toString</code> 方法。</li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">var</span> num = <span class="number">100</span>;</span><br><span class="line"><span class="keyword">var</span> bool = <span class="literal">true</span>;</span><br><span class="line"><span class="built_in">console</span>.log(<span class="keyword">typeof</span> num.toString());</span><br><span class="line"><span class="built_in">console</span>.log(<span class="keyword">typeof</span> bool.toString());</span><br></pre></td></tr></table></figure>

<h1 id="运算符"><a href="#运算符" class="headerlink" title="运算符"></a>运算符</h1><h2 id="基本运算"><a href="#基本运算" class="headerlink" title="基本运算"></a>基本运算</h2><ul>
<li>当数字与任意字符串都相加时相当于字符串拼接</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="number">100</span> + <span class="string">&quot;100&quot;</span>);</span><br><span class="line"><span class="comment">//结果为 100100</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">100</span> + <span class="string">&quot;test&quot;</span>);</span><br><span class="line"><span class="comment">//结果为 100test</span></span><br></pre></td></tr></table></figure>

<ul>
<li>当数字与一个字符串类型的数字相减时就返回正确的结果，与非数字的字符串相见返回 NAN</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="number">100</span> - <span class="string">&quot;10&quot;</span>);</span><br><span class="line"><span class="comment">//结果为 90</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">100</span> - <span class="string">&quot;test&quot;</span>);</span><br><span class="line"><span class="comment">//结果为NaN</span></span><br></pre></td></tr></table></figure>

<ul>
<li>乘法、除法与减法类似</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="number">100</span> * <span class="string">&quot;test&quot;</span>);</span><br><span class="line"><span class="comment">//结果为 NaN</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">100</span> * <span class="string">&quot;10&quot;</span>);</span><br><span class="line"><span class="comment">//结果为 1000</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">100</span> / <span class="string">&quot;test&quot;</span>);</span><br><span class="line"><span class="comment">//结果为 NaN</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">100</span> / <span class="string">&quot;10&quot;</span>);</span><br><span class="line"><span class="comment">//结果为 10</span></span><br></pre></td></tr></table></figure>

<div class="note success simple"><p>加法运算时，无论字符串是什么都会进行拼接；而减法、除法、乘法则会尽力转换字符串为 number 类型，如果无法转换结果为 NaN，否则返回运算结果</p>
</div>

<h2 id="取余运算"><a href="#取余运算" class="headerlink" title="取余运算"></a>取余运算</h2><ul>
<li>当左边的操作数位正数时，那么结果也为正数</li>
<li>当左边的操作数位负数时，那么结果也为负数</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="number">10</span> % <span class="number">3</span>);</span><br><span class="line"><span class="comment">//结果为 1</span></span><br><span class="line"><span class="built_in">console</span>.log(-<span class="number">10</span> % <span class="number">3</span>);</span><br><span class="line"><span class="comment">//结果为 -1</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">10</span> % -<span class="number">3</span>);</span><br><span class="line"><span class="comment">//结果为 1</span></span><br><span class="line"><span class="built_in">console</span>.log(-<span class="number">10</span> % -<span class="number">3</span>);</span><br><span class="line"><span class="comment">//结果为 -1</span></span><br></pre></td></tr></table></figure>

<h2 id="自增运算"><a href="#自增运算" class="headerlink" title="自增运算"></a>自增运算</h2><ul>
<li>自增 (自减) 运算结果的确定其实很简单，因为 <code>n++</code> 是 <code>n=n+1</code> 的简写，所以当加号在后边的时候 <code>n++</code> 那么返回的是<code>n</code>，也就是直接返回结果在计算。反之，当 <code>++n</code> 时返回的就是运算结果`</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">var</span> n = <span class="number">100</span>;</span><br><span class="line"><span class="keyword">var</span> result1 = n++;</span><br><span class="line"><span class="comment">//result 的值为n的值 因为加号在后边，所以返回n而不是返回运算后的值</span></span><br><span class="line"><span class="built_in">console</span>.log(result1, n);</span><br><span class="line"><span class="comment">// result1为100 n为101</span></span><br></pre></td></tr></table></figure>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">var</span> n = <span class="number">100</span>;</span><br><span class="line"><span class="keyword">var</span> result = ++n;</span><br><span class="line"><span class="comment">//result 的值为n运算后的结果 因为加号在前边，所以返回n运算的结果</span></span><br><span class="line"><span class="built_in">console</span>.log(result, n);</span><br><span class="line"><span class="comment">// result为101 n为101</span></span><br></pre></td></tr></table></figure>

<h2 id="全等与不等运算"><a href="#全等与不等运算" class="headerlink" title="全等与不等运算"></a>全等与不等运算</h2><ul>
<li>判断是否为 NaN</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br></pre></td><td class="code"><pre><span class="line"><span class="built_in">console</span>.log(<span class="built_in">isNaN</span>(<span class="string">&#x27;test&#x27;</span>));</span><br><span class="line"><span class="comment">//NaN</span></span><br></pre></td></tr></table></figure>

<ul>
<li>只判断值而不判断类型</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">// 只判断值是否相等 相等返回true 不等返回false</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">2</span> == <span class="string">&quot;2&quot;</span>); <span class="comment">//true</span></span><br><span class="line"><span class="comment">// 只判断值是否不等于 不等于返回true 等于返回false</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">2</span> != <span class="string">&quot;2&quot;</span>); <span class="comment">//false</span></span><br></pre></td></tr></table></figure>

<ul>
<li>即判断值也判断类型</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">// 判断值与类型是否全相同 全相同返回true 不全相同返回false</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">2</span> === <span class="string">&quot;2&quot;</span>); <span class="comment">//false</span></span><br><span class="line"><span class="comment">// 判断值与类型是否不相同 不相同返回true 相同返回false</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="number">2</span> !== <span class="string">&quot;2&quot;</span>); <span class="comment">//true</span></span><br></pre></td></tr></table></figure>

<h1 id="流程控制"><a href="#流程控制" class="headerlink" title="流程控制"></a>流程控制</h1><h2 id="选择结构"><a href="#选择结构" class="headerlink" title="选择结构"></a>选择结构</h2><ul>
<li><strong>单分支结构</strong></li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">//单分支</span></span><br><span class="line"><span class="function"><span class="title">if</span>(<span class="params">判断条件</span>)</span>&#123;</span><br><span class="line">	代码段</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<ul>
<li><strong>双分支结构</strong></li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">//双分支</span></span><br><span class="line"><span class="function"><span class="title">if</span>(<span class="params">判断条件</span>)</span>&#123;</span><br><span class="line">   代码段<span class="number">1</span></span><br><span class="line">&#125;<span class="keyword">else</span>&#123;</span><br><span class="line">   代码段<span class="number">2</span></span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<ul>
<li><strong>多分支结构</strong></li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">//多分支</span></span><br><span class="line"><span class="function"><span class="title">if</span>(<span class="params">条件<span class="number">1</span></span>)</span>&#123;</span><br><span class="line">   代码段<span class="number">1</span>;</span><br><span class="line">&#125;<span class="keyword">else</span> <span class="function"><span class="title">if</span>(<span class="params">条件<span class="number">2</span></span>)</span>&#123;</span><br><span class="line">   代码段<span class="number">2</span>;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="title">switch</span>(<span class="params">表达式</span>)</span>&#123;</span><br><span class="line">   <span class="keyword">case</span> 值<span class="number">1</span>:</span><br><span class="line">   代码段<span class="number">1</span>;</span><br><span class="line">   <span class="keyword">break</span>;</span><br><span class="line">   <span class="keyword">case</span> 值<span class="number">1</span>:</span><br><span class="line">   代码段<span class="number">1</span>;</span><br><span class="line">   <span class="keyword">break</span>;</span><br><span class="line">   ...</span><br><span class="line">   <span class="keyword">default</span>: </span><br><span class="line">   代码段n;</span><br><span class="line">   &#125;</span><br></pre></td></tr></table></figure>

<h2 id="循环结构"><a href="#循环结构" class="headerlink" title="循环结构"></a>循环结构</h2><ul>
<li><strong>while循环</strong></li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="title">while</span>(<span class="params">循环条件</span>)</span>&#123;</span><br><span class="line">   循环体</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<ul>
<li><strong>do…while循环</strong></li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">do</span>&#123;</span><br><span class="line">   循环体</span><br><span class="line">&#125;<span class="keyword">while</span>(循环条件);</span><br></pre></td></tr></table></figure>

<ul>
<li><strong>for循环</strong></li>
</ul>
<figure class="highlight javascript"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="title">for</span>(<span class="params">初始条件;循环条件;迭代条件</span>)</span>&#123;</span><br><span class="line">   代码块</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<ul>
<li><strong>froEach循环</strong></li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">var</span> age = [<span class="number">12</span>,<span class="number">3</span>,<span class="number">4</span>,<span class="number">5</span>,<span class="number">12</span>,<span class="number">3</span>,<span class="number">14</span>,<span class="number">213</span>];</span><br><span class="line">age.forEach(<span class="function"><span class="keyword">function</span>(<span class="params">value</span>)</span>&#123;</span><br><span class="line">   <span class="built_in">console</span>.log(value);</span><br><span class="line">&#125;)</span><br></pre></td></tr></table></figure>

<ul>
<li><strong>跳转语句</strong><br>  break语句和continue语句</li>
</ul>
<figure class="highlight html"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br></pre></td><td class="code"><pre><span class="line">//实现九九乘法表</span><br><span class="line"><span class="tag">&lt;<span class="name">script</span>&gt;</span></span><br><span class="line"><span class="javascript"><span class="built_in">document</span>.write(<span class="string">&quot;&lt;h1&gt;九九乘法表&lt;/h1&gt;&quot;</span>)</span></span><br><span class="line"><span class="javascript"><span class="built_in">document</span>.write(<span class="string">&quot;&lt;table border=1px&gt;&quot;</span>)</span></span><br><span class="line"><span class="javascript"><span class="function"><span class="title">for</span>(<span class="params"><span class="keyword">var</span> i=<span class="number">1</span>;i&lt;<span class="number">10</span>;i++</span>)</span>&#123;</span></span><br><span class="line"><span class="javascript">   <span class="built_in">document</span>.write(<span class="string">&quot;&lt;tr&gt;&quot;</span>)</span></span><br><span class="line"><span class="javascript">      <span class="function"><span class="title">for</span>(<span class="params"> <span class="keyword">var</span> j=<span class="number">1</span>;j&lt;i;j++</span>)</span>&#123;</span></span><br><span class="line"><span class="javascript">         <span class="built_in">document</span>.write(<span class="string">&quot;&lt;td&gt;&quot;</span>)</span></span><br><span class="line"><span class="javascript">         <span class="built_in">document</span>.write(j+<span class="string">&quot;*&quot;</span>+i+<span class="string">&quot;=&quot;</span>+i*j);</span></span><br><span class="line"><span class="javascript">         <span class="built_in">document</span>.write(<span class="string">&quot;&lt;/td&gt;&quot;</span>)</span></span><br><span class="line">      &#125;</span><br><span class="line"><span class="javascript">         <span class="built_in">document</span>.write(<span class="string">&quot;&lt;/tr&gt;&quot;</span>)</span></span><br><span class="line">   &#125;</span><br><span class="line"><span class="tag">&lt;/<span class="name">script</span>&gt;</span></span><br><span class="line"></span><br></pre></td></tr></table></figure>

<h1 id="严格检查模式"><a href="#严格检查模式" class="headerlink" title="严格检查模式"></a>严格检查模式</h1><ul>
<li>ES6的特性</li>
</ul>
<figure class="highlight js"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta">&#x27;use strict&#x27;</span></span><br><span class="line"><span class="comment">// ES6局部变量，合法</span></span><br><span class="line"><span class="keyword">let</span> str1 = <span class="string">&quot;我是合法的&quot;</span>;</span><br><span class="line"><span class="comment">// 非ES6局部变量，合法</span></span><br><span class="line"><span class="built_in">console</span>.log(<span class="string">&quot;我是合法的&quot;</span>)</span><br><span class="line"><span class="keyword">var</span> str = <span class="string">&quot;我也是合法的&quot;</span>;</span><br><span class="line"><span class="built_in">console</span>.log(<span class="string">&quot;我也是合法的&quot;</span>);</span><br><span class="line"><span class="comment">// 全局变量，不合法，会被严格检查模式检查出来</span></span><br><span class="line">i = <span class="number">6</span>;</span><br><span class="line"><span class="built_in">console</span>.log(<span class="string">&quot;严格检查模式可以检查全局变量&quot;</span>)</span><br></pre></td></tr></table></figure></article><div class="post-copyright"><div class="post-copyright__author"><span class="post-copyright-meta">文章作者: </span><span class="post-copyright-info"><a href="mailto:undefined">小李博客</a></span></div><div class="post-copyright__type"><span class="post-copyright-meta">文章链接: </span><span class="post-copyright-info"><a href="https://xiaoliblog.cn">https://xiaoliblog.cn</a></span></div><div class="post-copyright__notice"><span class="post-copyright-meta">版权声明: </span><span class="post-copyright-info">本博客所有文章除特别声明外，均采用 <a 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card-announcement-animation"></i><span>公告</span></div><div class="announcement_content">正在考研备考中💦</div></div><div class="sticky_layout"><div class="card-widget" id="card-toc"><div class="item-headline"><i class="fas fa-stream"></i><span>目录</span></div><div class="toc-content"><ol class="toc"><li class="toc-item toc-level-1"><a class="toc-link" href="#JavaScript"><span class="toc-number">1.</span> <span class="toc-text">JavaScript</span></a><ol class="toc-child"><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%BC%95%E5%85%A5%E6%96%B9%E5%BC%8F"><span class="toc-number">1.1.</span> <span class="toc-text">引入方式</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%BC%82%E6%AD%A5%E5%8A%A0%E8%BD%BD"><span class="toc-number">1.2.</span> <span class="toc-text">异步加载</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E8%BE%93%E5%87%BA%E8%AF%AD%E5%8F%A5"><span class="toc-number">1.3.</span> <span class="toc-text">输出语句</span></a></li></ol></li><li class="toc-item toc-level-1"><a class="toc-link" href="#%E6%95%B0%E6%8D%AE%E7%B1%BB%E5%9E%8B"><span class="toc-number">2.</span> <span class="toc-text">数据类型</span></a><ol class="toc-child"><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%8C%85%E8%A3%85%E7%B1%BB%E5%9E%8B"><span class="toc-number">2.1.</span> <span class="toc-text">包装类型</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E7%89%B9%E6%AE%8A%E7%B1%BB%E5%9E%8B"><span class="toc-number">2.2.</span> <span class="toc-text">特殊类型</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#undefined"><span class="toc-number">2.2.1.</span> <span class="toc-text">undefined</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#null"><span class="toc-number">2.2.2.</span> <span class="toc-text">null</span></a></li></ol></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E7%B1%BB%E5%9E%8B%E8%BD%AC%E6%8D%A2"><span class="toc-number">2.3.</span> <span class="toc-text">类型转换</span></a><ol class="toc-child"><li class="toc-item toc-level-3"><a class="toc-link" href="#%E9%9A%90%E5%BC%8F%E7%B1%BB%E5%9E%8B%E8%BD%AC%E6%8D%A2"><span class="toc-number">2.3.1.</span> <span class="toc-text">隐式类型转换</span></a></li><li class="toc-item toc-level-3"><a class="toc-link" href="#%E6%98%BE%E5%BC%8F%E7%B1%BB%E5%9E%8B%E8%BD%AC%E6%8D%A2"><span class="toc-number">2.3.2.</span> <span class="toc-text">显式类型转换</span></a></li></ol></li></ol></li><li class="toc-item toc-level-1"><a class="toc-link" href="#%E8%BF%90%E7%AE%97%E7%AC%A6"><span class="toc-number">3.</span> <span class="toc-text">运算符</span></a><ol class="toc-child"><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%9F%BA%E6%9C%AC%E8%BF%90%E7%AE%97"><span class="toc-number">3.1.</span> <span class="toc-text">基本运算</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%8F%96%E4%BD%99%E8%BF%90%E7%AE%97"><span class="toc-number">3.2.</span> <span class="toc-text">取余运算</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E8%87%AA%E5%A2%9E%E8%BF%90%E7%AE%97"><span class="toc-number">3.3.</span> <span class="toc-text">自增运算</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%85%A8%E7%AD%89%E4%B8%8E%E4%B8%8D%E7%AD%89%E8%BF%90%E7%AE%97"><span class="toc-number">3.4.</span> <span class="toc-text">全等与不等运算</span></a></li></ol></li><li class="toc-item toc-level-1"><a class="toc-link" href="#%E6%B5%81%E7%A8%8B%E6%8E%A7%E5%88%B6"><span class="toc-number">4.</span> <span class="toc-text">流程控制</span></a><ol class="toc-child"><li class="toc-item toc-level-2"><a class="toc-link" href="#%E9%80%89%E6%8B%A9%E7%BB%93%E6%9E%84"><span class="toc-number">4.1.</span> <span class="toc-text">选择结构</span></a></li><li class="toc-item toc-level-2"><a class="toc-link" href="#%E5%BE%AA%E7%8E%AF%E7%BB%93%E6%9E%84"><span class="toc-number">4.2.</span> <span class="toc-text">循环结构</span></a></li></ol></li><li class="toc-item toc-level-1"><a class="toc-link" href="#%E4%B8%A5%E6%A0%BC%E6%A3%80%E6%9F%A5%E6%A8%A1%E5%BC%8F"><span class="toc-number">5.</span> <span class="toc-text">严格检查模式</span></a></li></ol></div></div><div class="card-widget card-recent-post"><div class="item-headline"><i class="fas fa-history"></i><span>最新文章</span></div><div class="aside-list"><div class="aside-list-item"><a class="thumbnail" href="/page/project01.html" title="前端实例🥳响应式网站首页"><img src="https://cdn.jsdelivr.net/gh/xiaoliblog/image@c19917500ab083c77c7613263ba7ee74d5a08ae6/2021/04/30/469f30b141d73fa0fc4c962662d5813f.png" onerror="this.onerror=null;this.src='https://cdn.jsdelivr.net/gh/lzyblog/image@main/2020/11/19/bd16b394f7359083b1f6072a67e3f968.png'" alt="前端实例🥳响应式网站首页"/></a><div class="content"><a class="title" href="/page/project01.html" title="前端实例🥳响应式网站首页">前端实例🥳响应式网站首页</a><time datetime="2021-04-30T11:50:53.094Z" title="发表于 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    user: 'xiaoliblog',
    fixed: 'fixed',
    px: 'px',
    x: '',
    y: '',
    span1: '',
    span2: '',
    month: ['一月', '二月', '三月', '四月', '五月', '六月', '七月', '八月', '九月', '十月', '十一月', '十二月'],
    monthchange: [],
    oneyearbeforeday: '',
    thisday: '',
    amonthago: '',
    aweekago: '',
    weekdatacore: 0,
    datacore: 0,
    total: 0,
    datadate: '',
    data: [],
    positionplusdata: [],
    firstweek: [],
    lastweek: [],
    beforeweek: [],
    thisweekdatacore: 0,
    mounthbeforeday: 0,
    mounthfirstindex: 0,
    crispedges: 'crispedges',
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    amonthagoindex: 0,
    amonthagoweek: [],
    firstdate: [],
    first2date: [],
    montharrbefore: [],
    monthindex: 0,
    color: ['#ebedf0', '#f1f8ff', '#dbedff', '#c8e1ff', '#79b8ff', '#2188ff', '#0366d6', '#005cc5', '#044289', '#032f62', '#05264c']
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var apiurl = 'python-github-calendar-api-ruby.vercel.app' ? 'https://python-github-calendar-api-ruby.vercel.app/api?' : 'https://githubapi.ryanchristian.dev/user/'
var githubapiurl = apiurl + gitcalendar.user;
//canvas绘图
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          y: 0
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    ctx.fillText("二", 0, 3.9 * linemaxwitdh);
    ctx.fillText("四", 0, 5.9 * linemaxwitdh);
    ctx.fillText("六", 0, 7.9 * linemaxwitdh);
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    };
    cmessage.onmousemove = function(event) {
      document.querySelector('.angle-wrapper').style.display = 'none'
    };
    c.onmousemove = function(event) {
      document.querySelector('.angle-wrapper').style.display = 'none'
      getMousePos(c, event);
    };

    function getMousePos(canvas, event) {
      var rect = canvas.getBoundingClientRect();
      var x = event.clientX - rect.left * (canvas.width / rect.width);
      var y = event.clientY - rect.top * (canvas.height / rect.height);
      //console.log("x:"+x+",y:"+y);
      for (let item of gitcalendar.positionplusdata) {
        let lenthx = x - item.x;
        let lenthy = y - item.y;
        //console.log(lenthx,lenthy);
        if (0 < lenthx && lenthx < lineminwitdh) {
          if (0 < lenthy && lenthy < lineminwitdh) {
            //console.log(item.date,item.count)
            document.querySelector('.angle-wrapper').style.display = 'block'
            gitcalendar.span1 = item.date;
            gitcalendar.span2 = item.count;
            gitcalendar.x = event.clientX - 100;
            gitcalendar.y = event.clientY - 60
          }
        }
        //if(0< x - item.x <lineminwitdh&&0< y - item.y <lineminwitdh){
        //console.log(item.count,item.date);
        //}
      }
    }
  }
}
//数据统计算法
function addlastmonth() {
  if (gitcalendar.thisdayindex === 0) {
    thisweekcore(52);
    thisweekcore(51);
    thisweekcore(50);
    thisweekcore(49);
    thisweekcore(48);
    gitcalendar.thisweekdatacore += gitcalendar.firstdate[6].count;
    gitcalendar.amonthago = gitcalendar.firstdate[6].date
  } else {
    thisweekcore(52);
    thisweekcore(51);
    thisweekcore(50);
    thisweekcore(49);
    thisweek2core();
    gitcalendar.amonthago = gitcalendar.first2date[gitcalendar.thisdayindex - 1].date
  }
};

function thisweek2core() {
  for (let i = gitcalendar.thisdayindex - 1; i < gitcalendar.first2date.length; i++) {
    gitcalendar.thisweekdatacore += gitcalendar.first2date[i].count
  }
};

function thisweekcore(index) {
  for (let item of gitcalendar.data[index]) {
    gitcalendar.thisweekdatacore += item.count
  }
};

function addlastweek() {
  for (let item of gitcalendar.lastweek) {
    gitcalendar.weekdatacore += item.count
  }
};

function addbeforeweek() {
  for (let i = gitcalendar.thisdayindex; i < gitcalendar.beforeweek.length; i++) {
    gitcalendar.weekdatacore += gitcalendar.beforeweek[i].count
  }
};

function addweek(data) {
  if (gitcalendar.thisdayindex === 6) {
    gitcalendar.aweekago = gitcalendar.lastweek[0].date;
    addlastweek()
  } else {
    lastweek = data.contributions[51];
    gitcalendar.aweekago = lastweek[gitcalendar.thisdayindex + 1].date;
    addlastweek();
    addbeforeweek()
  }
}

fetch(githubapiurl)
  .then(data => data.json())
  .then(data => {
    gitcalendar.data = data.contributions;
    gitcalendar.total = data.total;
    gitcalendar.first2date = gitcalendar.data[48];
    gitcalendar.firstdate = gitcalendar.data[47];
    gitcalendar.firstweek = data.contributions[0];
    gitcalendar.lastweek = data.contributions[52];
    gitcalendar.beforeweek = data.contributions[51];
    gitcalendar.thisdayindex = gitcalendar.lastweek.length - 1;
    gitcalendar.thisday = gitcalendar.lastweek[gitcalendar.thisdayindex].date;
    gitcalendar.oneyearbeforeday = gitcalendar.firstweek[0].date;
    gitcalendar.monthindex = gitcalendar.thisday.substring(5, 7) * 1;
    gitcalendar.montharrbefore = gitcalendar.month.splice(gitcalendar.monthindex, 12 - gitcalendar.monthindex);
    gitcalendar.monthchange = gitcalendar.montharrbefore.concat(gitcalendar.month);
    addweek(data);
    addlastmonth();
    responsiveChart();
  })
  .catch(function(error) {
    console.log(error);
  });

//手机版更换为svg绘制
if (document.getElementById("gitcalendarcanvasbox").offsetWidth < 500) {
  gitcalendar.simplemode = false
}

//当改变窗口大小时重新绘制canvas
window.onresize = function() {
  if (gitcalendar.simplemode) responsiveChart()
}

//解决滚动滑轮时出现的标签显示
window.onscroll = function() {
  if (document.querySelector('.angle-wrapper')) {
    document.querySelector('.angle-wrapper').style.display = 'none'
  }
};</script></div><script src="/live2dw/lib/L2Dwidget.min.js?094cbace49a39548bed64abff5988b05"></script><script>L2Dwidget.init({"pluginRootPath":"live2dw/","pluginJsPath":"lib/","pluginModelPath":"assets/","tagMode":false,"log":false,"model":{"jsonPath":"/live2dw/assets/hijiki.model.json"},"display":{"position":"right","width":150,"height":300},"mobile":{"show":true},"react":{"opacity":0.7}});</script></body></html>